Counter with cipher block chaining messaging authentication code (CCM) is a known protocol for encrypting data and enabling the encrypted data to be authenticated. The CCM algorithm uses a symmetric key block cipher algorithm as a component building block; the CCM algorithm can therefore be viewed as a mode of operation of the symmetric key block cipher. Examples of symmetric key block ciphers include the advanced encryption standard (AES) and the data encryption standard (DES).
More and more data traffic over the Internet is being encrypted by a number of cipher algorithms, with some data transmission standards, such as the IEEE 802.16 wireless standard, specifying the use of the CCM algorithm. As part of making their inventions, the inventors recognize that the CCM algorithm and the underlying block cipher would dramatically increase the computational demands on the central processing units of network servers, particularly the central processing units that implement the network protocol layer and the media-access control layer.